Recovery from Turfgrass Dormancy
Dormant turfgrasses recover rapidly upon receipt of good soaking rains accompanied by cooling of the air and soil. The photographs below delineate a lawn in summer dormancy (Fig. 9.7) compared to the same lawn following cooler temperatures and after receiving ample rainfall (Fig. 9.8). Kentucky bluegrasses, fine fescues, perennial ryegrasses and tall fescues, all are able to withstand a certain amount of summer drought without major damage and do naturally recover when growing conditions again become favorable.
Figure 9.7. Dormant turfgrass as a result of prolonged warm and dry conditions.
Figure 9.8. Recovery of dormant turfgrass due to ample rainfall and cooler temperatures
Because it takes some time to establish a balance between top growth and root growth following dormancy, it's good to let the lawn grow taller before resuming normal mowing practices. However, even with letting the grass grow taller initially, do not remove more than one-third of the grass plant height in any one mowing during this recovery period. If the grass is taller than the normal desired height, gradually reducing it back to that level will be less stressful for the grass plants. Do not encourage rapid foliage development with excessive nitrogen fertilizer applications. As growth conditions improve and turfgrasses increase in vigor, core aeration on compacted soils will help improve potential rooting depth thereby improving the plant’s capacity to tolerate future stressful conditions.
While lawns developed and established to be sustainable usually require less water inputs, carelessly neglecting water needs of the grass plants may destroy all the effort put into creating a sustainable lawn ecosystem. Maintaining grass plant health is still the major objective of any lawn care program. Supplying supplemental water as needed remains a sound management practice for the lawn and the environment.